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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

All commands from sorted by
Terminal - All commands - 12,378 results
wget --server-response --spider http://www.example.com/
2009-03-31 18:49:14
User: penpen
Functions: wget

Let me suggest using wget for obtaining the HTTP header only as the last resort because it generates considerable textual overhead. The first ellipsis of the sample output stands for

Spider mode enabled. Check if remote file exists.

--2009-03-31 20:42:46-- http://www.example.com/

Resolving www.example.com...

Connecting to www.example.com||:80... connected.

HTTP request sent, awaiting response...

and the second one looks for

Length: 438 [text/html]

Remote file exists and could contain further links,

but recursion is disabled -- not retrieving.

lynx -dump -head http://www.example.com/
2009-03-31 18:41:36
User: penpen

Without the -dump option the header is displayed in lynx. You can also use w3m, the command then is

w3m -dump_head http://www.example.com/
ssh -vN hostname 2>&1 | grep "remote software version"
2009-03-31 18:28:41
User: sud0er
Functions: grep hostname ssh
Tags: ssh

I used this to confirm an upgrade to an SSH daemon was successful

date +%m/%d/%y%X|tr -d 'n' >>datemp.log&& sensors|grep +5V|cut -d "(" -f1|tr -d 'n'>> datemp.log && sensors |grep Temp |cut -d "(" -f1|tr -d 'n'>>datemp.log
2009-03-31 18:13:23
User: f241vc15
Functions: cut date grep sensors tr
cat datemp.log


Sys Temp: +11.0?C

CPU Temp: +35.5?C

AUX Temp: +3.0?C

find . -type f -exec grep StringToFind \{\} --with-filename \;|sed -e '/svn/d'|sed -e '/~/d'
2009-03-31 18:09:31
User: f241vc15
Functions: find grep sed

Look for a string in one of your codes, excluding the files with svn and ~ (temp/back up files). This can be useful when you're looking for a particular string in one of your source codes for example, inside a directory which is under version control (e.g. svn), removing all the annoying files with ~ (tilde) from the search. you can even change the command after -exec to delete (rm) or view (cat) files found by 'find' for example

curlftpfs ftp://YourUsername:[email protected] /tmp/remote-website/ && rsync -av /tmp/remote-website/* /usr/local/data_latest && umount /tmp/remote-website
2009-03-31 18:01:00
User: nadavkav
Functions: rsync umount

connect to a remote server using ftp protocol over FUSE file system, then rsync the remote folder to a local one and then unmount the remote ftp server (FUSE FS)

it can be divided to 3 different commands and you should have curlftpfs and rsync installed

wget --http-user=YourUsername --http-password=YourPassword http://YourWebsiteUrl:2082/getbackup/backup-YourWebsiteUrl-`date +"%-m-%d-%Y"`.tar.gz
2009-03-31 17:50:41
User: nadavkav
Functions: wget

this will connect to your hosted website service through the cPanel interface and use its backup tool to backup and download the entire website, locally.

(do not forget to replace : YourUsername , YourPassword and YourWebsiteUrl for it to work )

nmap -PN -T4 -p139,445 -n -v --script=smb-check-vulns --script-args safe=1
2009-03-31 15:15:17
User: cowholio4

This was posted on reddit. replace with the IP's you want to check.

awk '{print > $3".txt"}' FILENAME
2009-03-31 15:14:13
User: alperyilmaz
Functions: awk

This command will sort the contents of FILENAME by redirecting the output to individual .txt files in which 3rd column will be used for sorting. If FILENAME contents are as follows:

foo foo A foo

bar bar B bar

lorem ipsum A lorem

Then two files called A.txt and B.txt will be created and their contents will be:


foo foo A foo

lorem ipsum A lorem

and B.txt will be

bar bar B bar

rev <<< 'lorem ipsum' | tee /dev/stderr | rev
2009-03-31 13:12:09
User: penpen
Functions: rev tee
Tags: Linux unix

In the above example 'muspi merol' (the output of the first rev command) is sent to stderr and 'lorem ipsum' (the output of the second rev command) is sent to stdout. rev reverse lines of a file or files. This use of tee allows testing if a program correctly handles its input without using files that hold the data.

ssh [email protected] "(cd /path/to/remote/top/dir ; tar cvf - ./*)" | tar xvf -
2009-03-31 13:08:45
User: dopeman
Functions: ssh tar
Tags: copy files

This command will copy files and directories from a remote machine to the local one.

Ensure you are in the local directory you want to populate with the remote files before running the command.

To copy a directory and it's contents, you could:

ssh [email protected] "(cd /path/to/a/directory ; tar cvf - ./targetdir)" | tar xvf -

This is especially useful on *nix'es that don't have 'scp' installed by default.

ps aux | sort +2n | tail -20
2009-03-31 12:03:34
User: dopeman
Functions: ps sort tail

This command will show the 20 processes using the most CPU time (hungriest at the bottom).

You can see the 20 most memory intensive processes (hungriest at the bottom) by running:

ps aux | sort +3n | tail -20

Or, run both:

echo "CPU:" && ps aux | sort +2n | tail -20 && echo "Memory:" && ps aux | sort +3n | tail -20
man ascii
[[ $(COLUMNS=200 ps faux | awk '/grep/ {next} /ssh -N -R 4444/ {i++} END {print i}') ]] || nohup ssh -N -R 4444:localhost:22 [email protected] &
2009-03-31 09:39:59
User: j0rn
Functions: awk nohup ps ssh
Tags: ssh cronjob

I find it ugly & sexy at the same time isn't it ?

rm -rf ~/.local/share/Trash/files/*
date -d @$(echo $((2 ** 31 - 1)))
2009-03-30 19:42:20
User: jnash
Functions: date echo


Some other notable dates that have passed:

date [email protected] date [email protected]
alias rot13="tr '[A-Za-z]' '[N-ZA-Mn-za-m]'"
2009-03-30 19:08:49
User: penpen
Functions: alias
Tags: Linux unix

rot13 maps a..mn..z (A..MN..Z) to n..za..m (n..za..m) and so does this alias.

mkdir() { /bin/mkdir $@ && eval cd "\$$#"; }
alias l='ls -CFlash'
2009-03-30 17:11:31
Functions: alias

create a short alias for 'ls' with multi-column (-C), file type syntax additions (slashes after directories, @ for symlinks, etc... (-F), long format (-l), including hidden directories (all ./, ../, .svn, etc) (-a), show file-system blocks actually in use (-s), human readable file sizes (-h)

cat /var/log/secure | grep smtp | awk '{print $9}' | cut -f2 -d= | sort | uniq -c | sort -n | tail
2009-03-30 15:49:54
User: empulse
Functions: awk cat cut grep sort uniq

Searches /var/log/secure for smtp connections then lists these by number of connections made and hosts.

cat /var/log/secure | grep sshd | grep Failed | sed 's/invalid//' | sed 's/user//' | awk '{print $11}' | sort | uniq -c | sort -n
2009-03-30 15:48:24
User: empulse
Functions: awk cat grep sed sort sshd uniq

Searches the /var/log/secure log file for Failed and/or invalid user log in attempts.

whiptail --checklist "Simple checkbox menu" 11 35 5 tag item status repeat tags 1
2009-03-30 12:21:48
Tags: ncurses,

Not so much handy by itself, but very nice in shell scripts.

This makes you a handy ncurses based checklist. Much like terminal installers, just use the arrow keys and hit 'Space' to adjust the selections. Returns all selected tags as strings, with no newline at the end. So, your output will be something like:

"one" "two" "three" "four" "etc"

For those who prefer bash expansion over gratuitious typing:

whiptail --checklist "Simple checkbox menu" 12 35 3 $(echo {one,two,three,four}" '' 0"} )

Things to note:

The height must includes the outer border and padding: add 7 to however many items you want to show up at the same time.

If the status is 1, it will be selected by default. anything else, will be deselected.

du -xk | sort -n | tail -20
2009-03-30 11:37:43
User: dopeman
Functions: du sort tail

This command will tell you the 20 biggest directories starting from your working directory and skips directories on other filesystems. Useful for resolving disk space issues.

Printing portion of a big file
2009-03-30 11:08:38
User: acirulli
Tags: sed

If you need to print some portion of a huge file, let's say you want to print from line 200 to 300, you can use this command to print the line from LINE1 to LINE2 of file FILE.

pinfo date
2009-03-30 10:05:56
User: atoponce

The pinfo package makes info pages much more bearable. It is a ncurses-based POSIX utility for viewing info and man pages using lynx style keyboard shortcuts and rendering. Links are highlighted blue, the current location of your cursor is red. Navigating and searching are easy. Worth the install.